Despite strong U.S. sales of models like the new Accord, Honda's bottom line results disappointed analysts and investors.

Honda’s bottom line took an unexpected hit during the latest quarter, the third-largest Japanese maker reporting that earnings slid 7% compared to the year before despite increased sales outside its home market and the boost Japanese makers, in general, have been getting from a weaker yen.

Honda reported a net profit of 122.4 billion yen, or $1.25 billion during the April-June period – the first quarter in the Japanese fiscal year. A survey of industry analysts by FactSet showed a consensus forecast of 146 billion yen, or $1.5 billion.

That was particularly true in Japan, where Honda delivered just 140,000 vehicles during the quarter, down from 185,000 during the prior year. On the other hand, sales tracked almost precisely with the overall upturn of the American market, growing 7.1%, to 407,927. Worldwide, sales rose a modest 1%, to 858,000.

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Honda officials remain upbeat for the full fiscal year – which ends on March 31, 2014 – predicting sales will grow more than 10%, from 4 million to 4.43 million. It meanwhile expects to see revenues for the year grow to 12.1 trillion yen, with an operating profit of 780 billion yen. It also held to its earlier forecast of a 580 billion yen, or $5.9 billion net profit – which would be up 60% from the previous fiscal year.

The latest quarter actually got an estimated 83 billion yen, or $847 million, boost from shifting exchange rates that saw the yen drop to an average of around 100 to the dollar during the latest quarter compared to just 80 a year ago.

The maker also got a helping hand from increased motorcycle sales.

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But that wasn’t enough to offset increased spending on both R&D and on new plants. The maker has been racing to bring a trio of new hybrid drivetrains to market, for one thing. And it is shifting still more of its production base off the Japanese home islands despite the weakening yen.

Honda was just one of several Japanese makers to reveal first-quarter numbers today. Mazda delivered a striking turnaround from its year ago loss, when it reported 6.46 billion yen of red ink. For the latest April to June quarter it said it earned 5.46 billion yen, or $55.7 million. That was, however, well under the 7.76 billion yen consensus forecast, cautioned FactSet.

Meanwhile, Fuji Heavy industries nearly tripled its prior year numbers with a 48.5 billion yen profit, up from 16.4 billion yen a year before. The parent of the Subaru brand expects to see a 10% gain in net earnings for the full fiscal year.

Nissan Motor Co. was the first of the big Japanese automakers to weigh in, reporting an 82 billion, or $820 million, net on Monday, a 10 billion yen jump. The maker credited several factors that included a 14% increase in U.S. sales, as well as the weakened yen.

Industry sales leader Toyota is planning to release its own financial results on Friday.